• Title of article

    Measurements of 4He in metal-poor extragalactic H ii regions: the primordial Helium abundance and the ΔY/ΔO ratio

  • Author/Authors

    Manuel Peimbert، نويسنده , , A. Peimbert، نويسنده , , L. Carigi، نويسنده , , V. Luridiana، نويسنده ,

  • Issue Information
    روزنامه با شماره پیاپی سال 2009
  • Pages
    10
  • From page
    91
  • To page
    100
  • Abstract
    We present a review on the determination of the primordial helium abundance Yp , based on the study of hydrogen and helium recombination lines in extragalactic H ii regions. We also discuss the observational determinations of the increase of helium to the increase of oxygen by mass ΔY/ΔO, and compare them with predictions based on models of galactic chemical evolution.
  • Keywords
    H II regions , irregular , early universe , ISM: abundances , Galaxy: disk , Evolution , galaxies: abundances
  • Journal title
    Proceedings of the International Astronomical Union
  • Serial Year
    2009
  • Journal title
    Proceedings of the International Astronomical Union
  • Record number

    675096